People affected by Ataxia with vitamin E deficiency (AVED) have difficulty absorbing, metabolising and storing vitamin E from the diet. When cells are deficient in Vitamin E they are vunerable to damage - expecially the nerve cells found in the brain and spinal cord. The breakdown of these important nerves causes problems with movement and other features of AVED.
The type of gene variation can influence the type of symptoms and condition severity and there can also be some variability between members of the same family. Symptoms include neurological problems such as difficulty coordinating movements and speech, loss of reflexes in the legs, and a loss of sensation in the extremities. Other features can include tremor, vision problems, and heart disease.
Symptoms of AVED often appear in late childhood or early teens. Early initiation of treatment, before symptoms manifest, can prevent many complications. Treatment after symptoms appear can prevent further decline; it is possible for some symptoms, including ataxia and intellectual deterioration, to be reversed. If left untreated, affected individuals often require a wheelchair support.
As humans we have about 23,000 genes. These genes are like tiny instruction manuals that influence our health, growth and development. We inherit half of our genes from our biological mum and the other half from our biological dad. These genes are lined up on structures called chromosomes. Most of us have 23 pairs of chromosomes. The first 22 pairs are called autosomes and for the most part - these are the same among men and women. The 23rd pair determine our sex - two X chromosomes for a female and one X and one Y chromosome for males.
ataxia with vitamin E deficiency is known as an autosomal recessive condition. For autosomal recessive conditions, if a person has a variation in one copy of their gene, they are a carrier. This means that they are healthy because they also have a working copy of the gene. But, they can still pass their non-working copy to their child.
If the other parent also happens to be a carrier of the same gene, there is a 25% (1 in 4) chance that they both pass this gene variation on to their child — and as such, have a child affected by the condition.
If both parents are carriers of ataxia with vitamin E deficiency, there's a one in four chance that their children could develop symptoms.
Carrier testing is like a checkup for your genes. It tests to see if you carry a gene variation that could cause a serious genetic condition in your child. Eugene offers an inclusive genetic carrier screening panel that includes ataxia with vitamin E deficiency, but there's a total 301 conditions that can be tested.
Eugene's carrier test is a clinical grade test that can be done from the comfort of your own home — it's just a saliva test. You're also paired with a genetic counsellor who provides mindful support and guidance every step of the way.Learn more about carrier screening
The biggest benefit of screening for ataxia with vitamin E deficiency is that it can help future parents understand their reproductive risk so they can be ready and empowered to make more informed decisions. If neither partner are carriers, it provides reassurance and peace of mind that the risk of having a child with a genetic condition is low.
Since 90% of children that have a recessive genetic condition like ataxia with vitamin E deficiency had no previous family history of it, it often feels completely out of the blue for the parents. Getting screened is a way to know this risk in advance, which can help familes manage or even prevent the condition in the first place.